Атмосферная циркуляция в индоокеанском секторе Восточной Антарктиды за последние 200 лет по данным изучения химического состава снежно‑фирнового покрова

Spatial and temporal variability of a sea‑salt aerosol (Na+) concentration was investigated in snow‑firn cores and snow pits taken at four sites of the Indian Ocean sector of the East Antarctica (along a profile between stations Progress and Vostok: PV‑10, NVFL‑1, SW‑42, and the Vostok point). In long annually resolved Na+ records, we had revealed the following periodicities: 17 to 95‑year (Vostok) and 29 to 52‑year (NVFL‑1), while the shorter records are characterized by 8‑year periodicity. The Na+ concentrations decrease as the snow accu‑ mulation increases (especially, at the Vostok station), and this is evidence for a presence of «dilution effect» in the sites with the great part of «dry precipitation». The closest relationship was revealed between changes in flows of Na+ at points SW‑42, and PV‑10. Variability of the Na+ fluxes had been linked to the circulation indices (AAO, PDO, SOI, MEI, SPO) and the sea level pressure in the Southern Hemisphere, as well as to occurrence of Elementary Circulation Mechanisms (ECM). The revealed irregularity of the Na+ precipitation over the area under investigation is caused by different atmospheric circulation patterns as well as by influ‑ ence of basic Action Centers of the Atmosphere (ACA) in the Southern Hemisphere. The closest relationship is found to take place with South Pacific ACA (Vostok, 1976–2009) and with the South Indian ACA (SW‑42 and PV‑10). A presence of distant atmospheric relations (including one with El Nino) had been revealed for the inland areas. Changes in features of the atmospheric circulation in the South Indian Ocean over the last 200‑year period have been reconstructed on the basis of summarized Na+ records from the Vostok station area. Distinctive feature of the atmospheric circulation is the 40‑year periodicity with its increasing intensity during the following periods: 1805–1820, 1830–1860, 1890–1900, 1940–1950, and 1980–2000. In addition, we had revealed that changes in the atmospheric circulation in the Indian Ocean (Southern Hemisphere) were synchronous with similar variability of the circulation in the Siberian (Northern Hemisphere) sector.По данным изучения химического состава снежно-фирнового покрова в индоокеанском секторе Восточной Антарктиды установлены пространственно-временные изменения аккумуляции морского аэрозоля (Na+). Исследованы корреляционные связи аккумуляции Na+ с индексами циркуляции и полем давления Южного полушария, а также элементарными циркуляционными механизмами. Впервые выполнена реконструкция интенсивности региональной циркуляции за последние 200 лет

Ice core chemistry database: an Antarctic compilation of sodium and sulfate records spanning the past 2000 years

Changes in sea ice conditions and atmospheric circulation over the Southern Ocean play an important role in modulating Antarctic climate. However, observations of both sea ice and wind conditions are limited in Antarctica and the Southern Ocean, both temporally and spatially, prior to the satellite era (1970 onwards). Ice core chemistry data can be used to reconstruct changes over annual, decadal, and millennial timescales. To facilitate sea ice and wind reconstructions, the CLIVASH2k (CLimate Variability in Antarctica and the Southern Hemisphere over the past 2000 years) working group has compiled a database of two species, sodium [Na+] and sulfate [SO2− 4 ], commonly measured ionic species. The database (https://doi.org/10.5285/9E0ED16E-F2AB4372-8DF3-FDE7E388C9A7; Thomas et al., 2022) comprises records from 105 Antarctic ice cores, containing records with a maximum age duration of 2000 years. An initial filter has been applied, based on evaluation against sea ice concentration, geopotential height (500 hPa), and surface wind fields to identify sites suitable for reconstructing past sea ice conditions, wind strength, or atmospheric circulation

Химический состав приземного атмосферного аэрозоля в Баренцбурге (архипелаг Шпицберген) по результатам многолетних исследований

The chemical composition (ions, elements, polycyclic aromatic hydrocarbons) of aerosol and gaseous impurities (SO2, HNO3, HCl, NH3) in the surface layer of the atmosphere in Barentsburg, located on the Western Svalbard island (Svalbard archipelago), is analyzed. Atmospheric aerosol and gaseous impurities brought to the Arctic from middle latitudes and deposited on snow and ice not only interact with various natural objects, but also spread to long distances with melting dirty snow and ice. Air sampling was carried out following to methodology adopted by the international networks of the atmospheric monitoring programs in South-East Asia (EANET) and Europe (EMEP). In 2011-2015, the observations of the chemical composition of the atmospheric ground layer were performed daily during the light season (April–September), and monthly from April 2016 to 2018. The largest total ion concentrations were observed in 2011–2012. Seasonal variability of ion concentrations in the aerosol was characterized by high values in the cold period (October–February) and low values in the warm one (May–June). High values of the coefficient of correlation between ions Na+ and Cl− (r = 0,93) as well as between Mg2+ and Cl−  (r = 0,81) throughout the year show that the main source of the aerosol is the sea surface. The significant correlation between ions K+, NO3-, NH4+, SO42−, K+, SO42− in the polar night point to the influence of local sources: coal mining at the mine and its3 combustion at thermal power plants. Emission of polycyclic aromatic hydrocarbons and the gaseous impurities (SO2, HNO3) into the atmosphere, especially during the polar night, is also influenced by local sources. Among the elements the maximum enrichment of the aerosol was revealed for As, Cr, Zn, Mo, Cd, Sn, Sb, W, and Pb with a low content of Cd, Sn, Sb, W, and Pb in the coal, sludge and on the underlying surface. On the basis of the elemental composition of the aerosol and the back-trajectory analysis, it was shown that the air masses enriched in heavy metals come to the area of the Barentsburg settlement from middle latitudes.Прослежена межгодовая (2011–2017 гг.) и сезонная (2016–2018 гг.) изменчивость компонентов химического состава (ионы, элементы, полициклические ароматические углеводороды) атмосферного аэрозоля и газообразных примесей (SO2, HNO3, HCl, NH3) в приземной атмосфере западной части Российской Арктики (пос. Баренцбург на Шпицбергене)

Ice core chemistry database: an Antarctic compilation of sodium and sulfate records spanning the past 2000 years

Changes in sea ice conditions and atmospheric circulation over the Southern Ocean play an important role in modulating Antarctic climate. However, observations of both sea ice and wind conditions are limited in Antarctica and the Southern Ocean, both temporally and spatially, prior to the satellite era (1970 onwards). Ice core chemistry data can be used to reconstruct changes over annual, decadal, and millennial timescales. To facilitate sea ice and wind reconstructions, the CLIVASH2k (CLimate Variability in Antarctica and the Southern Hemisphere over the past 2000 years) working group has compiled a database of two species, sodium [Na+] and sulfate [SO2− 4 ], commonly measured ionic species. The database (https://doi.org/10.5285/9E0ED16E-F2AB4372-8DF3-FDE7E388C9A7; Thomas et al., 2022) comprises records from 105 Antarctic ice cores, containing records with a maximum age duration of 2000 years. An initial filter has been applied, based on evaluation against sea ice concentration, geopotential height (500 hPa), and surface wind fields to identify sites suitable for reconstructing past sea ice conditions, wind strength, or atmospheric circulation

Atmospheric circulation in the Indian Ocean sector of East Antarctica over the last 200 years according to chemical studies of snow‑firn cover

Spatial and temporal variability of a sea‑salt aerosol (Na+) concentration was investigated in snow‑firn cores and snow pits taken at four sites of the Indian Ocean sector of the East Antarctica (along a profile between stations Progress and Vostok: PV‑10, NVFL‑1, SW‑42, and the Vostok point). In long annually resolved Na+ records, we had revealed the following periodicities: 17 to 95‑year (Vostok) and 29 to 52‑year (NVFL‑1), while the shorter records are characterized by 8‑year periodicity. The Na+ concentrations decrease as the snow accu‑ mulation increases (especially, at the Vostok station), and this is evidence for a presence of «dilution effect» in the sites with the great part of «dry precipitation». The closest relationship was revealed between changes in flows of Na+ at points SW‑42, and PV‑10. Variability of the Na+ fluxes had been linked to the circulation indices (AAO, PDO, SOI, MEI, SPO) and the sea level pressure in the Southern Hemisphere, as well as to occurrence of Elementary Circulation Mechanisms (ECM). The revealed irregularity of the Na+ precipitation over the area under investigation is caused by different atmospheric circulation patterns as well as by influ‑ ence of basic Action Centers of the Atmosphere (ACA) in the Southern Hemisphere. The closest relationship is found to take place with South Pacific ACA (Vostok, 1976–2009) and with the South Indian ACA (SW‑42 and PV‑10). A presence of distant atmospheric relations (including one with El Nino) had been revealed for the inland areas. Changes in features of the atmospheric circulation in the South Indian Ocean over the last 200‑year period have been reconstructed on the basis of summarized Na+ records from the Vostok station area. Distinctive feature of the atmospheric circulation is the 40‑year periodicity with its increasing intensity during the following periods: 1805–1820, 1830–1860, 1890–1900, 1940–1950, and 1980–2000. In addition, we had revealed that changes in the atmospheric circulation in the Indian Ocean (Southern Hemisphere) were synchronous with similar variability of the circulation in the Siberian (Northern Hemisphere) sector

Investigation of Transport and Transformation of Tropospheric Ozone in Terrestrial Ecosystems of the Coastal Zone of Lake Baikal

Forest ecosystems play an important role in the process of removing trace gases from the atmosphere. The purpose of this work is the experimental study of the flux and rate of the dry deposition of ozone on different types of vegetation in the Baikal region. Based on the eddy covariance method and the flux gradient methods (including the aerodynamic gradient method (AGM), the modified Bowen method (MBR) and modified gradient method (MGM)) and with experimental data, the quantitative estimates of the fluxes and dry deposition velocity of ozone on the underlying surface were obtained for different environments (grasslands, forest). The average values of the dry deposition velocity of ozone (Vd) were equal to 0.37 cm/s at night (0–3 h) and 0.91 cm/s during daytime hours (12–18 h). The ozone flux (F) was 0.24 μg m–2 s–1 at night and 0.72 μg m–2 s–1 in the afternoon. The quantitative estimates of Vd and F on vegetation and in the forest show a higher absorptive capacity of forests compared to soil vegetation

Sea level fluctuations and their signature in the composition and structure of polygonal wedge ice in the Yenisei River lower reaches

Late Pleistocene and Holocene polygonal-wedge ice is studied in the lower course of the Yenisei River. Ice distribution, features of the formation, chemical and microbiological composition were determined. It was established that ice wedges were formed on the slopes of the depression, in coastal-marine lagoons and in thermokarst during Holocene. The evidence of thermoabrasion and thermokarst in sediments as well as the marine signal in composition of polygonal-wedge ice allowed clarifying the southern limit of the Holocene transgression

Chemical composition of the near-surface atmospheric aerosol in Barentsburg (Svalbard) based on the long-term observations

The chemical composition (ions, elements, polycyclic aromatic hydrocarbons) of aerosol and gaseous impurities (SO2, HNO3, HCl, NH3) in the surface layer of the atmosphere in Barentsburg, located on the Western Svalbard island (Svalbard archipelago), is analyzed. Atmospheric aerosol and gaseous impurities brought to the Arctic from middle latitudes and deposited on snow and ice not only interact with various natural objects, but also spread to long distances with melting dirty snow and ice. Air sampling was carried out following to methodology adopted by the international networks of the atmospheric monitoring programs in South-East Asia (EANET) and Europe (EMEP). In 2011-2015, the observations of the chemical composition of the atmospheric ground layer were performed daily during the light season (April–September), and monthly from April 2016 to 2018. The largest total ion concentrations were observed in 2011–2012. Seasonal variability of ion concentrations in the aerosol was characterized by high values in the cold period (October–February) and low values in the warm one (May–June). High values of the coefficient of correlation between ions Na+ and Cl− (r = 0,93) as well as between Mg2+ and Cl−  (r = 0,81) throughout the year show that the main source of the aerosol is the sea surface. The significant correlation between ions K+, NO3-, NH4+, SO42−, K+, SO42− in the polar night point to the influence of local sources: coal mining at the mine and its3 combustion at thermal power plants. Emission of polycyclic aromatic hydrocarbons and the gaseous impurities (SO2, HNO3) into the atmosphere, especially during the polar night, is also influenced by local sources. Among the elements the maximum enrichment of the aerosol was revealed for As, Cr, Zn, Mo, Cd, Sn, Sb, W, and Pb with a low content of Cd, Sn, Sb, W, and Pb in the coal, sludge and on the underlying surface. On the basis of the elemental composition of the aerosol and the back-trajectory analysis, it was shown that the air masses enriched in heavy metals come to the area of the Barentsburg settlement from middle latitudes